NBC (and the producers) chose not to tease the surprising family twist at the end in the lead-up, instead, focusing on the fact that all the characters happened to share the same birthday. But we all knew there was more to the story than that, right?

We’re breaking down each character and how they all fit together. Don’t worry, we’ll get to that surprising ending…

Kevin

Photo: NBC

Hollywood heartthrob and playboy (Justin Hartley), star of the successful fictional comedy The Man-ny, is going through an identity crisis. Dreading his 36th birthday, Kevin seeks more fulfillment from his superficial life, which includes all the women a sort-of B-list star can surround himself with.

After having an on-set meltdown following creative disagreements with The Man-ny’s unforgiving executive producer, who threatens him with every famous Ryan in Hollywood (Gosling, Phillippe, etc.), Kevin abruptly quits the show. And of course, his breakdown makes headline news on the Internet and entertainment news shows. Oops. Kevin takes solace in his twin sister, Kate, also celebrating her 36th birthday, who shares their father’s advice in hard times: “There’s no lemons so sour that you can’t make something resembling lemonade.”
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Kate

Photo: NBC

Kate’s (Chrissy Metz) struggles with her weight are just one part of her season-long journey. She’s also desperate to find her soulmate, meeting a potential suitor in Toby (Chris Sullivan) at a weight-loss support group she attends. Though she plays hard to get, Kate and Toby go on a romantic date and leaves the door open for a possible relationship as the series progresses.

A happily married father of two, Randall (Sterling K. Brown) seeks out his biological father, William (Ron Cephas Jones), who abandoned him at the fire station when he was a baby and eventually meets him. (His mom, he reveals, was a crack addict.) Though Randall is financially stable, has a good job and is raising a good family, he makes a point to tell his father all that he’s accomplished in his life and is filled with a mixture of emotions (hurt, regret, pride) over it.

Randall doesn’t hesitate to welcome his biological father into his home, but gets the shock of a lifetime when he learns William is dying, which certainly throws a wrench into their future. Of Randall’s journey moving forward, Brown had this to say to ET: “I’m very curious to explore the idea of an African-American man being raised by a white family, and what does that mean in certain cultural touchstones? Did he grow up eating soul food, or did his wife introduce him to soul food later in life?”
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Photo: NBC

Rebecca and Jack
Introduced as a married couple in Pittsburgh expecting triplets, there’s an early hint that they may not be from the present day -- as the show opens, a camera pans over a cardboard box with “Family Photos ’75-‘79” scrawled on it. Things don’t go according to plan when Rebecca’s (Mandy Moore) water breaks on the day of her husband Jack’s (Milo Ventimiglia) birthday.

Everything seems to be moving along until complications during labor -- due to the high-risk nature of the pregnancy -- cause Rebecca to lose one of their babies, who is stillborn. Their plan for a family of five is temporarily halted, but it’s their doctor’s (Gerald McRaney) wisdom that helps Jack see the light. “You took the sourest lemons that life has to offer and turned it into something resembling lemonade,” he said. Sound familiar?

How are all the characters connected, you ask? Rebecca and Jack -- whose arc is revealed to take place in the recent past (presumably in 1979) -- are parents to Kevin, Kate and Randall, the abandoned baby from the fire station they end up adopting that day at the hospital.

Meet the “Big Three” then…

Photo: NBC

And now…

Photo: NBC

How’s that for a mother of a twist? That’s how they all share the same birthday. Genius, right?

It will be interesting to see how This Is Us pushes forward its storylines and how closely tied they are to the format established in the pilot. Will Rebecca and Jack’s arc as new parents provide the framework for each episode? Have Rebecca and Jack long passed in the present day? Will Kevin, Kate and Randall’s worlds collide on a more regular basis?
The mystery won’t be solved until week two (and likely beyond), but we sure can’t wait to go on the ride!

Tell us what you thought about the This Is Us premiere and the surprising family twist by tweeting @ETnow!